Revolvable hair curling iron

ABSTRACT

A hair curling iron for curling hairs is disclosed which includes a handle for housing a motor and a first member having a first end rotatably coupled to the handle and selectively driven into rotation by the motor. The first member has a second end spaced from the first end in a direction of elongation. The hair curling iron further includes a heating element disposed within the first member and extending partially in the direction of elongation between the first end and the second end and a clamp mounted for rotation with the first member, the clamp having a closed position suitable for retaining the hairs and an open position suitable for receiving and withdrawing the hairs.

CROSS-REFERENCE TO RELATED APPLICATIONS

Priority is claimed under 35 U.S.C. §119 to U.S. Provisional Application Ser. No. 60/661,748, filed on Mar. 14, 2005. The contents of this Provisional Application is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to hand-held hair-styling appliances. In particular, the present invention relates to a hair-curling appliance that is electrically heated and includes a motor to wind and unwind hair, to curl hair automatically.

BACKGROUND OF THE INVENTION

Heated styling irons are commonly used to style hair to a wide variety of styles, such as by curling hair to impart a curl that does not naturally occur in the hair and by straightening hair to remove a kink or curl that does naturally occur in that hair. For example, a circular or semicircular-shaped curl can be created by wrapping hair about the outer surface of a heated cylindrically shaped curling iron tip.

Conventional curling irons include a curling mandrel comprising a generally cylindrical, elongated curling bar having a clamping member adapted to fit about a portion of the circumference thereof for at least a portion of the length thereof. During use, the curling mandrel is heated and a strand of hair is clamped against the bar by the clamping member. Manual rotation of the entire curling iron winds the remainder of the strand of hair about the mandrel. The heat in the mandrel alters the texture of the hair so as to curl it and after a predetermined amount of time, the curled hair is unwound.

One of the greatest difficulties encountered in the use of a curling iron is that of winding the hair about the mandrel. Winding is typically a slow process in which the entire curling iron must be manually rotated. Such winding requires the use of two hands thereby making it difficult for a person to set their own hair. Rotating the entire device may also result in tangling of the power cord or the need for the power cord to have an independent swivel connection to the curling iron. Furthermore, since the degree of curl is dependent upon the temperature of the mandrel and the time of contact therewith, such winding should be rapidly or consistently accomplished in order to allow for uniform curl formation and to prevent burning of portions of the hair; however, this is difficult to perform when the device must be manually rotated. Accordingly, there is a need for a curling iron having a driven mandrel which will simplify the winding of the hair thereabout.

SUMMARY OF THE INVENTION

In one aspect of the invention, a hair curling iron for curling hairs is disclosed which includes a handle for housing a motor and a first member having a first end rotatably coupled to the handle and selectively driven into rotation by the motor. The first member has a second end spaced from the first end in a direction of elongation. The hair curling iron further includes a heating element disposed within the first member and extending partially in the direction of elongation between the first end and the second end and a clamp mounted for rotation with the first member, the clamp having a closed position suitable for retaining the hairs and an open position suitable for receiving and withdrawing the hairs.

In a further aspect of the invention, the hair curling iron also includes a clutch rotatably coupled between the motor and the first member wherein the first member and the clutch rotate for so long as the drag on the first member is less then a prescribed value.

These and other aspects, features and advantages, shall be apparent from the accompanying drawing figures and description of certain embodiments thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements.

FIG. 1 is a perspective view of a particular hair styling appliance structured in accordance with the principals of the present invention in a closed position;

FIG. 2 is a side view of the hair styling appliance of FIG. 1;

FIG. 3 is an exploded view of the styling appliance of FIG. 1 illustrating the major components thereof;

FIG. 4 is a bottom view of the hair styling appliance of FIG. 1 a broken away to show internal components;

FIG. 5 is a schematic diagram of a magnetic reed relay structured in accordance with a further aspect of the present invention; and

FIG. 6 is a block diagram of control circuitry structured in accordance with a salient aspect of the present invention.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

The present invention provides a curling iron constructed and suitable for heating and revolving hair into a curl which is set by the heat and contours of the curling iron. Referring to FIGS. 1 and 2, curling iron 10 is shown in a closed position and generally includes a curling mandrel 12 and a handle 22. The mandrel 12 includes an electrically heated male member 20. Additionally, mandrel 12 is motor driven to allow for rotation in a clockwise or counterclockwise direction to aid in curling of hair around the mandrel. The mandrel 12 includes an elongated, generally cylindrical male member 20 having a clamping element (female member 28) in contact with at least a portion of the circumference thereof. The female member 28 is an elongated element which is preferably pivotally attached to a bezel 65 (FIG. 3) at a pivot point 34. Bezel 65 is rotatably mounted between handle 22 and male member 20. Female member 28 includes a projecting contact portion 29 which can be used to move the female member 28 to an open position wherein the curved portion thereof is pivoted out of engagement with the male member 20. Projecting portion 29 is adapted to bias the female member 28 between the open position and a closed position to enable retention and release of one or more strands of hair. For example, a spring 62 can be connected to the female member 28 to movably bias the female member to the closed position and to resist movement of the female member to the opened position.

The handle 22 of the curling iron 10 can be provided with a power cable 40 (as shown) or can be battery driven. The handle preferably includes a switch 16 for controlling power to the device. An indicator light 30 is provided on housing 22 for indicating when the curling iron 10 is being heated. Handle 22 further includes a motor switch 32 for initiating and terminating rotation of the mandrel 12. The motor switch 32 may further be adapted to control the direction of mandrel rotation and it should be understood that different arrangements for the switches can be provided for control over heating and the motor. It will be noted that curling iron 10 is configured so that the components thereof are disposed along a common linear central axis so as to provide a linear appliance. The particular arrangement of the components of the curling iron readily adapts it for either right or left-handed operation with equal facility. Male and female members, 20 and 28, respectfully, are configured to project axially from handle 22. Handle 22 is preferably provided with an ergonomic shape and is made of heat resistant material for gripping by the user.

During operation of the curling iron 10, the power cord 40 is connected to a source of electrical energy. In accordance with salient aspects of a curling iron in accordance with the present invention, a heat level selector switch can be provided to control an appropriate level of heat, typically a high or low level, and a motor speed selection switch can be provided so as to choose a desired mandrel rotational speed, typically a high, medium or low speed. In order to curl hair, switch 16 is first turned on to heat curling iron 10. Once sufficiently heated, projecting portion 29 of female member 28 is depressed to open the female member 28. One or more strands of hair are inserted between female member 28 and male member 20, and projecting portion 29 is then released so as to retain the strands of hair. The motor actuating switch 32 is then activated to rotate the mandrel 12 and wind the hair about the mandrel. Once the hair is fully wound, motor control switch 32 is again pressed to terminate rotation.

After an amount of time sufficient to heat-set the curls in the hair, the motor rotation switch 32 can be again activated to reverse the direction of mandrel 12 rotation so as to unwind the hair therefrom; and/or the projecting portion 29 can be depressed so as to release the now curled strands of hair.

In a variation of the foregoing, the mandrel 12 may simply be disengaged from the motor at the end of the curling time, so as to spin free of the motor. In this embodiment a slight pull on the curling iron can allow the mandrel to rotate freely thereby unwinding the curled hair. Such modification is readily accomplished by including a release clutch 60 (FIG. 3) for disengaging the mandrel 12 from the motor 102. Clutch 60 is rotatably coupled between the motor and the male member 20 and the male member and the clutch rotate together for so long as the drag on the male member is less then a prescribed value, but the clutch permits slippage of the motor shaft while the mandrel stays stationary if the drag exceeds the value.

Referring now to FIG. 3, there is shown an exploded view of a curling iron 10 generally similar to that illustrated with reference to FIGS. 1 and 2. The curling iron 10 includes a handle 22 which doubles as a housing for the internal components of the curling iron. Handle 22 houses an electric motor 102 adapted to rotate curling mandrel 12. The male member 20 has a first end rotatably coupled to handle 22 and selectively driven into rotation by the motor and a second end spaced from the first end in a direction of elongation. The motor 102, which may be a conventional stepper motor, is coupled to a clutch assembly 60 having an adapter shaft 65 adapted to engage a portion of the mandrel 12 through bezel 67. Bezel 67 is rotatably mounted to handle 22.

The clutch 60 is preferably a spring loaded face plate type of clutch and is adapted to slip if the load on the motor 102 becomes too great. The clutch 60 is a safety feature which prevents damage to the motor or injury to the user in the event that hair becomes caught in the rotating mandrel 12 or the motor control switch 32 fails. In such instances, the clutch will allow for slippage, thereby preventing harm or damage.

The mandrel 12 includes a heating element 42 disposed within the male member 20 in a generally coaxial relationship with the circumference thereof and extending partially in the direction of elongation between the first end and the second end of the male member 20. Heating element 42 is composed of material that has a high heat conducting efficiency and is fixed relative to the first and second ends of the male member. As shown, plural holes can be formed on its surface to improve the efficiency of heat-conductivity. Heating element 42 has an axis extending in the direction of elongation of male member 20. Male member 20 is coupled to the housing so as to rotate parallel to or coincident with this axis. A heating device (not shown), such as an electric or gas-burning heater, can be mounted within handle 22 for heating heating element 42. For details on a gas burning heater, see co-pending U.S. Provisional Application Ser. Nos. 60/717,575, 60/752,115 and 60/764,991 entitled “Cordless Hairdryer with Movable Baffle,” filed, Sep. 14, 2005, Dec. 19, 2005 and Feb. 2, 2006, respectively, the entirety of which are hereby incorporated by reference.

There is also disposed an indicator lamp 30 in series with the heating element 42 for indicating when the heating element 42 is energized. The lamp 30 can be an incandescent lamp, a gas discharge lamp such as a neon lamp, a light emitting diode LED or the like. In other embodiments, the mandrel 12 may have thermochromic material placed thereupon, to indicate by suitable color change when a proper hair curling temperature is reached.

Electrical power is communicated to the motor 102 via the switch 32. The switch 32 can provide preselected levels of power to the motor. Optionally, the switch 32 can continuously vary the power to the motor or it may be a stepwise acting switch adapted to provide various levels, as for example high, medium and low levels of power to the motor. Other combinations of speed and/or heat settings can be utilized. All such modifications should be apparent to one of skill in the art in light of the disclosure herein.

The operation of the projecting portion 29 is to bias the female member 28 between an open and closed position. Female portion 28 has a central opening therein and is disposed so that the male member 20 passes through the central opening. Female member 28 and its projecting portion 29 are preferably composed of a temperature-resistant material exhibiting a low coefficient of friction, among such materials are metals and various synthetic polymers such as nylon, Dehrin, Teflon, and the like.

Female member 28 preferably defines a “crescent” shaped cross-section. Referring to FIG. 1, when hair styling device 10 is in the closed position male member 20 forms a nested concave/convex relationship with the female member 28 partially covering the male member 20. Male member 20 has a generally circular-shaped cross-section and female member 28 has a generally crescent-shaped cross-section. Thus, when members 20 and 28 are brought into contact with each other the convex face of male member 20 abuts the concave face of female member 28. Members 20, 28 can have smooth surfaces, lacking any bristle, rib, projection or other feature which might impede their movement through the hair 89. Preferably at least one of the male and female members includes a series of ribs disposed circumferentially about its surface. Such a series can be oriented at an angle relative to the direction of elongation and extend between the first and second ends.

The male member is preferably heated by the heating element 42 being located within it; however, in certain embodiments, male and female members 20, 28 are both heated or the heating element can be disposed in the female member 28.

The female member 28 has a spring 62 associated with the pivot point 34 thereof for purposes of biasing the female member 28 to its closed position. Release of a manual force on the projecting portion 29 allows the spring 62 to return the female member 28 to the closed position illustrated in FIG. 1.

With reference to FIGS. 3 and 4, motor 102 can be a DC motor. The use of a DC motor confers several advantages in curling irons. DC motors are typically small sized and therefore allow for lightweight, compact appliances having a linear configuration. Additionally, use of DC motors allows for the ready, electrical control of motor rotation so as to provide for simple control of mandrel rotation.

Surfaces 20 and 28 can grasp the trapped hair strands yet slide freely in a stroking manner from the scalp to the hair tips to accomplish a hair straightening effect. Slight rotation of hair styling appliance 10 as by cooking the user's wrist during the stroke, adds a flip to the hair.

As described above, members 20 and 28 are simultaneously rotated along the P axis to rotational angles in the range of 0° to 360°. As the rotational angle is rotated past 0° to an order of 180° or more, any hair 89 pressed between the male and female members is curled. Note that the term “press,” “pressed” or “pressing” as used herein describes closing the members 20, 28 of the hair styling apparatus 10 together to form an inside or anterior contact surface between the members in which any hair 89 is secured between the members.

Referring to FIG. 5, hair styling apparatus 10 includes magnetic reed relay 500 for monitoring the revolutions of the motor 102, and consequently the revolutions of the mandrel. This information can be used in a variety of ways, i.e., to detect motor malfunctions, count the number of mandrel revolutions, etc. A magnet 502 is connected to the motor shaft gear 504. As motor 102 drives the motor shaft gear 504 the magnet 502 comes into and out-of contact with the magnet reed relay 500. When magnet 502 reaches magnet reed relay 500 it causes contacts A and B to short circuit. Magnetic reed relay 500 can be connected to a microprocessor via contact A and B for detecting, for example, the short circuit of contacts A and B, thereby recording each revolution of the motor shaft gear 504.

Signals issued by the rotating shaft can comprise a magnetic field that selectively influences the magnet reed relay 500, e.g., to close the relay whenever the magnet is proximate the relay (e.g., in the 12 o'clock position as shown). Closure of the relay can interrupt power to the motor for a moment (as timed by suitable electronic circuitry or software) or until the switch 16 is activated again. In this way, the user can cease curling operations precisely at each complete rotation and be able to open female member and free the curled hair 89 from the hair styling appliance 10. More generally, circuitry can be provided to limit each actuation to a certain number of rotations or time of rotation for more precise curling control by the user.

Referring to FIG. 6, an example of suitable electronic circuitry for interrupting and controlling power to the motor is disclosed for the embodiment of FIG. 5. Specifically, a controller 700 with inputs for sensing closure of relay 500 via contacts A and B is provided. When the relay 500 is closed, control circuit 700 will output a signal on terminal 709 stopping the motor 102 for a predetermined time period set by RC circuit 703. The motor 102 can be reactivated by triggering switch 16 or, otherwise, waiting a prescribed time interval upon which control circuit 700 will automatically reactivate the motor 102. Accordingly, the above described arrangement will permit controllable reactivation of motor 102 after each full rotation of the mandrel. After each full rotation, the user will be given the choice to stop further curling and free the hair held thereby or to continue curling for another complete rotation.

The relay described above can be set upon activating the motor and reset when a short circuit signal is generated after the mandrel has rotated 360°, or vice versa. If for any reason the reset condition does not occur, such as if motor 102 experiences a jam or a power off condition occurs prior to a full 360° rotation of motor shaft gear 504, the relay will remain set informing the microprocessor that the motor has not completed its rotation and may have been unnecessarily prevented from completing its cycle.

Embodiments of the hair styling technology described herein may be applied to various other hair treating or styling devices for shaping hair, such as, curlers, clamp curling brushes, steam curlers, hair rollers, hot hair rollers, hair straighteners, hair flatteners, and curling wands. Furthermore, while specific embodiments of the hair styling appliance with concave/convex heating surfaces of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects.

While the invention has been described with reference to several embodiments thereof, the invention is more broadly defined and limited only by the recitations in the claims appended hereto and their legal equivalents. 

1. A hair curling iron for curling hairs, comprising: a handle; a motor within the handle; a first member having a first end rotatably coupled to the handle and selectively driven into rotation by the motor, and having a second end spaced from the first end in a direction of elongation; an elongated heating element disposed within the first member and extending partially in the direction of elongation between the first end and the second end; and a clamp mounted for rotation with the first member, the clamp having a closed position suitable for retaining the hairs and an open position suitable for receiving and withdrawing the hairs.
 2. The curling iron of claim 1, wherein the heating element is fixed relative to the first and second ends of the first member.
 3. The curling iron of claim 1, further comprising a clutch rotatably coupled between the motor and the first member.
 4. The curling iron of claim 3, wherein the motor has a shaft and wherein the first member and the clutch rotate for so long as the drag on the first member is less then a prescribed value and the first member and at least part of the clutch slip relative to the motor shaft if the drag on the first member is greater than the prescribed value.
 5. The curling iron of claim 1, wherein the heating element has an axis and wherein the first member is coupled to the housing so as to rotate parallel to or coincident with the axis.
 6. The curling iron of claim 1, wherein the first member comprises a heat conductor.
 7. The curling iron of claim 1, wherein the heating element includes a plurality of through-holes.
 8. The curling iron of claim 1, further comprising a control switch disposed on the handle to control activation and deactivation of at least one of the heating element and the motor.
 9. The curling iron of claim 1, further comprising a series of ribs disposed circumferentially about the clamp.
 10. The curling iron of claim 9, wherein the series of ribs comprises a single rib oriented at an angle relative to the direction of elongation and extending between the first and second ends.
 11. The curling iron of claim 1, wherein the clamp is pivotally mounted relative to the first member.
 12. The curling iron of claim 1, further comprising a bezel, the bezel being rotatably mounted to the handle and wherein the first member is mounted to the bezel.
 13. The curling iron as in claim 12, wherein the clamp is mounted to the bezel.
 14. The curling iron of claim 1, further comprising a spring connected to the clamp to movably bias the clamp to the closed position and to resist movement of the clamp to the opened position.
 15. The curling iron of claim 1, further comprising a tip connected to the second end of the first member.
 16. The curling iron of claim 1, further comprising: a relay circuit having an opened position and a closed position; a control circuit connected between the relay circuit and the motor, the control circuit having an input for sensing the closed position, wherein the control circuit is operable to output a deactivation signal to the motor when the relay is closed and reactivate the motor after a predetermined time period has passed.
 17. The curling iron of claim 16, wherein the relay closes for each full rotation of the first member.
 18. The curling iron of claim 1, further comprising a control switch disposed on the handle to provide preselected levels of power to the motor or to continuously vary the power to the motor.
 19. The curling iron of claim 1, further comprising a control circuit connected to the motor, the control circuit being programmed to intermittently rotate the motor in accordance with prescribed time intervals or rotations of the first member.
 20. The curling iron of claim 8, wherein the motor is a variable speed motor and the control switch is a motor speed selection switch for controlling the speed of the motor. 